Also, note, the accent is on the first syllable (chee) and the because there is a double c in there, you hold the middle 'ch' consanant a little longer.Imagine thinking in terms of musical beats.If it were a single c, it would be a two-beat word: chee-cha.But because it's a double c, think three beats, with the tongue resting on the inside of the top teeth/front-of-the-roof-of-your-mouth for that middle beat.Then, make that middle beat a little shorter than 3 even beats and you've got it.:-)

Confirming that BernalKC and Pauliface have it exactly right for standard Italian, which will certainly be acceptable. I don't know if there are any Sardinian dialect differences, but given BernalKC's experience I expect not.